From 1ea1860f53d2b1ef7e0faaea46829776a3297607 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <frederic@kernel.org>
Date: Mon, 6 Nov 2017 16:01:24 +0100
Subject: [PATCH] perf/core: Use lockdep to assert IRQs are disabled/enabled

References: bnc#1068202 Avoid irqs_disabled debugging checks in fast paths
Patch-mainline: v4.15-rc1
Git-commit: 164446455a5d3f1402b5a0ea42acce33fd576ed7

Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-9-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
 kernel/events/core.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 78de4fed1890..ffbdeedf77b2 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -209,7 +209,7 @@ static int event_function(void *info)
 	struct perf_event_context *task_ctx = cpuctx->task_ctx;
 	int ret = 0;
 
-	WARN_ON_ONCE(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 
 	perf_ctx_lock(cpuctx, task_ctx);
 	/*
@@ -306,7 +306,7 @@ static void event_function_local(struct perf_event *event, event_f func, void *d
 	struct task_struct *task = READ_ONCE(ctx->task);
 	struct perf_event_context *task_ctx = NULL;
 
-	WARN_ON_ONCE(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 
 	if (task) {
 		if (task == TASK_TOMBSTONE)
@@ -1008,7 +1008,7 @@ static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr)
 	struct perf_cpu_context *cpuctx;
 	int rotations = 0;
 
-	WARN_ON(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 
 	cpuctx = container_of(hr, struct perf_cpu_context, hrtimer);
 	rotations = perf_rotate_context(cpuctx);
@@ -1095,7 +1095,7 @@ static void perf_event_ctx_activate(struct perf_event_context *ctx)
 {
 	struct list_head *head = this_cpu_ptr(&active_ctx_list);
 
-	WARN_ON(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 
 	WARN_ON(!list_empty(&ctx->active_ctx_list));
 
@@ -1104,7 +1104,7 @@ static void perf_event_ctx_activate(struct perf_event_context *ctx)
 
 static void perf_event_ctx_deactivate(struct perf_event_context *ctx)
 {
-	WARN_ON(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 
 	WARN_ON(list_empty(&ctx->active_ctx_list));
 
@@ -3477,7 +3477,7 @@ void perf_event_task_tick(void)
 	struct perf_event_context *ctx, *tmp;
 	int throttled;
 
-	WARN_ON(!irqs_disabled());
+	lockdep_assert_irqs_disabled();
 
 	__this_cpu_inc(perf_throttled_seq);
 	throttled = __this_cpu_xchg(perf_throttled_count, 0);